Not can be should be. Liberty without life is not possible.
Why is it OK to abort babies who are conceived by rape? I understand that this is a most difficult situation to face personally. But the question is really a simple one, do you think that the sins of the father should always be visited on the son?
I've never met a republican, who wasn't a member of the Republican Party, or a democrat, who wasn't a member of the Democratic Party. Why should libertarians be any different?
In that case, if an indivdual leaves a political party, because of basic disagreements with that party's political platform, if it was me, I'd call myself an independent. Makes a lot more sense to me and keeps everyone from guessing what political party a certain person may, or may not associate with and allows that person to have a multitude of different beliefs and values.
Does that make any sense to you?
It makes total, rational and logical sense to me.